The apparatus of the present invention relates generally to the field of personnel safety and, more particularly, to means for protecting mining equipment operators from overhead falls and the like. To this end, the apparatus of the present invention comprehends the provision of a unique mining safety device of the canopy/cab type which is directly securable to one side of a mining machine for providing a safe enclosure from which an operator may operate the machine.
Occupational safety considerations for mining equipment operators, although a perhaps somewhat neglected area in the past, has recently been elevated to a critical concern and has been the subject of much emphasis in the industry. This heightened interest in projecting mining equipment operators from such dangers as roof falls and rib and face falls as well as rib and face rolls may be attributable at least in part to various rather recently enacted statutory requirements regulating all aspects of mining safety. In turn, the statutory regulations can in large part be traced to the increased public awareness of the dangerous conditions under which the nation's miners have been working for some time.
One area of major emphasis within the industry has been in the development, for use with self-propelled underground coal mining equipment such as shuttle cars, of variously configured cab and canopy structures. These cab and canopies are typically located and installed along one side of the mining machinery in such a manner that when the operator is at the operating controls of the equipment he is protected from falls of roof, face or rib or from rib and face rolls. In this regard, a canopy has been defined as a structure which provides overhead protection against falls of roof whereas cabs conventionally comprehend structures which additionally provide lateral protection against falls of rib and face or rib and face rolls. Exemplary of such structures, is the protective canopy disclosed in U.S. Pat. No. 3,937,517 issued Feb. 10, 1976 to Donovan et al.
Prior art cabs and/or canopies generally have been substantially rigid structures permanently and non-yieldably affixed to the mining machine and constructed so as to have a structural capacity for supporting given minimum loads. Although adjustable structures of this type are known in the art, the adjustability features are normally characterized by means primarily intended for enclosure positioning purposes such as, for example, to accommodate such factors as the height of the mine seam and the operator's visibility and comfort. Among other reasons, the non-yieldable relation between such prior art cabs and/or canopies contributes to a reduced impact absorbing capability whereby adequate protection for the machine operator is not provided.